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Physics: Blocks and ropes sample question

The eight figures show various situations where blocks of different weights are attached by ropes to rigidly fixed objects or to other blocks, which are attached to fixed objects. The situations differ in a number of ways, as the figures show, but all situations represent static equilibrium (i.e. nothing is moving). The weights of the blocks are given in the figures, as well as the magnitudes and directions of any other forces that may be acting. Our interest is solely in the rope that is designated R in each figure.

Which of the following statements are true about the situations depicted in the figures above? (Give ALL correct answers: B, AC, BCD.., or None )

A) The tension in the rope is greater in picture H than in picture C
B) The tension in the rope is equal in all pictures
C) The tension in the rope in picture G is 160 N
D) The tension in the rope is zero in pictures G and H
E) The tension in the rope is smaller in picture B than in picture D


Solution Preview

A) is false since it is clear that in picture C the tension is 80 N wether in picture H it is 40 + 40 = 80 N, hence both tensions are equal.
<br><br>B) clearly in picture E the tension is 100 N, hence we get according to A) that this case is different from H, hence the statement is false.
<br><br>C) This ...